Ledgerline

Double-entry books, invoicing, AI document capture, a CRM and a practice dashboard for Cyprus accountants and the companies they keep books for. It runs on this laptop: Next.js 16 with an embedded Postgres (PGlite) in .data/ledgerline, and no sign-in yet (one fixed demo user). The same code runs on Supabase: see Going live on Supabase. Every company, person and figure in it is fictional.

Start it

npm install                 # once
cp .env.example .env.local  # once, then put your key in it: ANTHROPIC_API_KEY=sk-ant-…
npm run demo:reset          # fresh demo data, build if needed, open http://localhost:3000
npm run demo                # the same, keeping whatever you did last time
npm run demo -- --build     # rebuild after changing code

No key yet? LEDGERLINE_AI_FIXTURES=1 npm run demo runs rehearsal mode: the four files in demo-files/ use readings recorded earlier, and Capture says "Rehearsal mode" in a yellow band. Explain the figures and Ask the books need the real key. Don't run rehearsal mode in the meeting.

Before the meeting: the key is in .env.local and was tested live on 22 Oct: the four demo files read in parallel in about 20 seconds, Explain the figures takes about 20 seconds and Ask the books about 10. Run npm run demo:reset so the meeting starts clean.

The demo, step by step (about 30 minutes)

The practice is Saltlake Accounting, a fictional Larnaca firm with six client companies, books from July 2025 to today, and October's bank lines left to reconcile.

1. Practice dashboard (/), 2 minutes

• "This is the practice, not one company." Six clients on one screen.
• Point at Aegean Blue Marine: its Jul–Sep VAT return is due 10 Nov, 19 days away, not filed, about €9,800 to pay. Cyprus quarters are staggered, so each client has its own due date; two clients aren't VAT registered (the dental clinic makes exempt supplies, the holding company only holds).
• 81 bank lines to reconcile, 3 documents waiting to review, overdue receivables per client, where each client's books are locked, last activity.
• Every figure is a link into that client's books.

1a. Who sees what (/sign-in), 1 minute

• Top right, your name → Sign in as someone else: the demo's people. Nikos Savva owns Pixelforge: he lands on its books, with no practice pages and no other client; Pixelforge's AML file isn't his to see. The database decides this, not the screens (row-level security).
• Back as Maria: Practice settings → People → Invite someone. The link is shown once; open it in a private window to join as the new person.

1b. A company's Home, 1 minute

• Open Larnaka Roast Coffee. One company at a time: the switcher at the top of the menu changes it and keeps the section you are in.
• The Home is for the person who runs the company: six large buttons (Raise an invoice, Record a bill, Upload a receipt, Money in, Money out, Write a quote), three figures (in the bank, customers owe you, you owe suppliers), one list of what needs attention, and the to-dos. The menu runs the way the owner works: CRM (enquiries, customers, quotes, invoices, products, jobs, tasks, calendar, each named the company's way), then Money (bank, receipts, bills, suppliers), then Reports & tax; the accountant's pages are under More.
• ⌘K (Ctrl+K, or /) from any page opens the command palette. Before anything is typed it offers what is usually done next (New invoice, Record a bill, Upload receipts…, in the company's own words: New patient at a clinic). Type and it finds actions, pages, companies by name, HE or VAT number, and the company's records: customers, invoices by number or customer, bills, quotes, suppliers, products, enquiries, jobs and employees, with their dates and amounts. Enter opens the one highlighted. At the practice it searches every client's records.

1b½. On a phone, 2 minutes

• Open http://localhost:3000 on a phone (or a narrow window) and sign in as Nikos Savva. A bar at the foot of the screen: Home, Invoices, +, Bank, Menu (the practice gets Dashboard, Deadlines and Clients).
• + opens what is done on the move: Snap a receipt opens the camera, and the photo is stored and read by Claude while the owner carries on; a note at the foot of the screen says when it is drafted as a bill, with Review. Or a new invoice, a bill, money in or out, a quote, a customer.
• The Home keeps to the two actions done most, the three figures and the first five things that need attention (Show all for the rest).
• Add to Home Screen (Safari's Share menu, or Chrome's Install) puts Ledgerline on the phone as an app with its own icon and window (src/app/manifest.ts, icons drawn in src/app/icons).
• Losing the connection shows a notice, and what was done meanwhile (a page opened, a form saved) waits and goes as soon as it is back (experimental.useOffline).

1b¾. In Greek, 2 minutes

• Sign in as someone else → Dr Sofia Hadjioannou, who owns Kalamies Dental and reads Ledgerline in Greek. The menu, Home, invoices, receipts, the command palette (type τιμολ), the phone's bar and +, and the messages at the foot of the screen are in Greek; so are the figures and dates (66.082,73 €, 28 Οκτ 2026, πριν από 3 ημέρες) and the deadlines (Προσωρινή φορολογία 2026, πρώτη δόση). The clinic's own words come through too: Ασθενείς και ασφαλιστικές.
• Each person chooses: the account menu, top right → Γλώσσα: English or Ελληνικά. It is theirs alone, wherever they sign in; the practice can read the same company in English.
• An amount is typed either way: 180,50 is a hundred and eighty and a half, as are 180.50 and 1.234,50 / 1,234.50 for the thousands.
• What goes to a customer follows the customer's language, not the screen's: the invoice by email, a payment reminder and the words before a shared link are in Greek for a customer whose documents are (Kalamies' are), in English for one whose are in English, in both for both.
• The accountant's pages (reports, journals, the chart, the practice's own) stay in English for now. npm run check:greek lists any phrase on a translated screen that is missing its Greek.

1c. Everyday work, 6 minutes

• Raise an invoice: choose a customer (or + New customer… and type a name). The number follows on (LRC-2026-0129), the due date comes from the company's terms (14 days here), and VAT follows the customer: standard for a Cyprus customer, reverse charge for an EU business, exempt if the company isn't registered.
• Lines with products: type "House espresso blend" in the description and the product fills in its price, VAT rate (5%) and income account. Set the quantity (20 kg), add a second product (Coffee service, 9%) and a third with Give a discount (10%). The totals show VAT at each rate. The arithmetic is exact: the database works every line out again when it saves.
• Save and issue: "Issued and in the books". View PDF is what the customer receives: quantities and units, unit prices, the discount, VAT by rate, the company's registration, how to pay. How it posted shows the double entry.
• Send: the covering email is written for you (the amount, the due date, the bank details and reference); Open in email opens it in your email app, ready to attach the PDF, and the invoice is marked as sent. Invoices not yet sent are listed under Not sent and on the Home.
• Share as a link (on an issued invoice, or a quote): a private link the customer opens without signing in, on their phone. They see what is owed and by when, the lines and VAT, the IBAN, BIC and reference to copy into their banking app, and Download PDF; nothing else of the books. Send it with WhatsApp (to the customer's own number when they have one), Viber, Text or Email: the message is written, with nothing to attach, and the invoice counts as sent. The panel says when they opened it ("Opened once, last 2 minutes ago"); See what they see previews it without counting, and Stop the link shuts it at once. The page wears the company's logo and colour.
• In Greek, or both: Company settings → How your documents look → Language (English, Ελληνικά, or both, Greek first), and any customer can have its own (Documents in, on the customer). The PDF is then written as Cypriot documents are: ΤΙΜΟΛΟΓΙΟ / INVOICE, Αρ. ΦΠΑ / VAT, ΑΦΤ / TIC, the payment instructions and the VAT wording in Greek (the reverse charge under άρθρο 196 της Οδηγίας 2006/112/ΕΚ), Greek capitals without their accents, and in Greek alone amounts and dates the Greek way (4.055,00 €, 10 Οκτ 2026); in both, dates as 26/11/2026. Kalamies Dental's documents are in Greek and Troodos Gold's in both. A shared link opens in Greek, with a tap away.

1d. Buying and paying, 3 minutes

• Bills: tick the overdue bills (Highland Green, Troodos Dairy, Ermou Street) and Pay them: choose the account and the day, and each bill is paid in full in the books. The payment run then offers Download the SEPA file: one ISO 20022 file (pain.001.001.03) to upload to the company's online banking, which sends all the transfers on that day. Suppliers without an IBAN are listed to pay another way. Checked on 22 Oct against the ISO schema. When the payments show on the statement, they match in one press.
• A supplier's credit note: the October Highland Green bill already has one (two damaged sacks), taken off what is still to pay. On any bill, More → Supplier credit note starts one from the bill's lines; it lowers the cost and the VAT reclaimed (box 4), and credit left over is used against their next bill or recorded as refunded into the bank.
• Suppliers carry an IBAN and BIC, checked as banks check them, an address, and their payment terms (a bill with no due date takes them).
• A supplier's statement (Highland Green → Statement): every bill, payment, credit note and refund in date order with the running balance, for any period (Everything gives the whole history, newest first if asked), or Open items on a day with how late each is. PDF and CSV; it agrees with the supplier page and with aged payables, as it stood on the day. Xero has no supplier statement at all.
• Check their statement (Troodos Dairy): type the balance their statement shows on its date beside ours; untick a payment of ours still on its way, tick a bill we dated after it, add one of theirs not in the books. At nothing left to explain it says Agreed. Kept with their statement (a PDF or a photo), on the supplier page and the audit trail. Neither Xero nor Sage does this without an add-on.
• Remittance advice: each payment, and each supplier in a payment run, has one as a PDF in the company's style, with the email written for you (Sage's can't be changed, and Xero's don't take its themes). Payment runs lists every run. Aged payables runs as at any day, credit not yet used coming off; each supplier opens its open items that day.

1d½. How documents look (Company settings → Documents), 2 minutes

• Larnaka Roast's Standard style: classic, its brown, a large logo, a payment slip to cut off, its own terms. Change opens the editor: layout (classic, modern, plain), sans or serif (Greek in both), size, A4 or US Letter, the logo left, centre or right and its size, headed paper, what shows, and each document's title ("Tax invoice") and terms. The preview beside it redraws the company's own latest invoice, quote, credit note, statement or remittance as it changes; nothing is kept until it is saved.
• Add a style, then give it to one customer on their page (Document style): their invoices, quotes, credit notes and statements take it, and everyone else keeps the default.

1e. Bringing a client's lists in, 1 minute

• Customers → Import (also Suppliers and Products): choose a spreadsheet saved as CSV, or paste it. The columns are recognised from their headings, in English or Greek, and can be changed; every row is checked and shown before anything is saved, and anyone already there is left alone. There is a template to download. Export gives each list back as a spreadsheet, and Invoices → Export all every invoice with what was paid and credited.

1f. The CRM, shaped to each business, 4 minutes

• Every company is set up from its kind of business, which the accountant picks when taking the client on: what it calls its customers and its work, the stages its enquiries and its work go through, the details it keeps, and which parts it uses. Switch company and watch the menu change:
  • Aegean Blue Marine (shipping): Clients, Enquiries, and Jobs that go Planned → In port → Final account → Closed, each with its vessel, port and ETA on the card.
  • Kalamies Dental (clinic): Patients and insurers, and Treatment plans (Proposed → Accepted → In treatment → Completed), with who pays.
  • Larnaka Roast (café and roastery): Orders, Received → Roasting → Ready → Delivered, collection or delivery on the card.
  • Troodos Gold (producer): Leads and Orders; Pixelforge (software studio): Deals and Projects with their fee basis; Mesogeios Holdings: only Opportunities and tasks, no quotes or jobs; Thames Edge Joinery: Jobs with the site address, opening in maps.
• The board: drag a card from stage to stage. Drop a deal on Won and it becomes a customer with its first job and first to-do (for a port agent, "Send the proforma disbursement account"); drop it on Lost and it asks why. Each column shows its value and how likely it is; the header, the pipeline's value and the likely part of it.
• Open any deal or customer: Call, WhatsApp, Viber or Email with the message started, and Save contact to the phone. Plain links: nothing to connect.
• Customise (under More): rename anything ("Jobs" to "Shipments"), add a stage, turn a part off, or add a detail of its own ("Pallets", on every card). Set by the company's owner or its accountant; its staff use it as set, and never see payroll.
• Tasks: everything to do, each with an owner and a date.
• Website form (Enquiries → Website form): Open the form shows the company's own form, in its logo and colour. Send one as a prospect, then go back to the board: it is in New, marked "From your website", owned by whoever had the fewest open enquiries, with a call-back task due the next working day. The same page has the snippet for the company's own site and the API call (POST /api/v1/enquiries); retires the old one at once. Enquiries nobody has answered for a day rise to the top of the board in red, and show on the company's Home.

1g. Deadlines (/deadlines), 2 minutes

• Every client's VAT returns, VIES statements, provisional tax, company tax returns and the balance of tax; payroll returns each month and the employer's annual TD7; the financial statements and the annual return (HE32) for the Registrar. All worked out from each company's VAT quarters, tax and financial years, incorporation date and the services the practice provides, with who looks after it. Nobody typed a deadline in.
• An official extension moves a date and says so: Kalamies' 2025 employer's return shows Extended from 31 May 2026 by the Tax Department, with the announcement linked.
• Overdue: Kalamies Dental's first provisional tax instalment slipped. It is also on Kalamies' Home. Mark done closes it.
• A VAT return closes itself when it is filed: file one from Open the return and it shows as Done. A VAT return still to file says how ready it is: bank lines in the quarter to match, documents to check.
• Inside a company, Deadlines (under Reports & tax) shows only its own. Who looks after a company is set in its Company settings.

1h. Time and fees (/time, /fees), 3 minutes

• Start timer in the top bar, on any page: it picks the company you are in. It keeps running as you move around, and stops in one press.
• Time: each person's week against their hours (Sofia is 2 hours over), the lighter part of each bar being time on clients. Add time worked without the timer; mark it Extra to bill it on top of the fee.
• Fees: each client's monthly fee against the hours its books took, as euros per hour, with the €40 floor as a dashed line. Kalamies Dental earns €32 an hour: reprice it. Raise October's fees invoices every client in one press from the firm's own books (Saltlake Accounting Ltd, under "Your firm's own books" in the company switcher), extra work included at each client's rate. Press again and nobody is billed twice.

1i. Taking on a client (/clients), 4 minutes

• Client files: every client's due diligence as ICPAC's AML Directive asks for it: risk rating, next review, and screening against the EU sanctions list. Mesogeios' review is a week overdue (it is on Deadlines too); Kalamies' is due in three weeks.
• Kypros Ferry Lines, won from the firm's own website form, is half way through being taken on. Send the engagement letter: it is written from the file (services, fee, the app) and fingerprinted. Copy the client's link and open it in a private window, or on a phone: no login. Sign it, and upload Alexander Petrov's proof of address (any PDF). Back on the file both are ticked, and the signed PDF carries the signature record.
• Screen everyone: the company and both owners are checked against the real EU consolidated list (6,269 people and entities). Alexander Petrov shares his name with two listed persons, born in 1958 and 1979: write why he is not them and Record the decision.
• Risk assessment: Ledgerline scores each factor from the file, as in ICPAC's guidance. The 40% owner's nationality is on the EU high-risk list, and an advocate introduced them: 9 of 20, normal risk, customer due diligence, reviewed every two years. Record the assessment, then Approve as compliance officer. A PEP, or an owner living in a high-risk country, makes it high risk whatever the score, approved by a partner.
• Take them on: open the books: the company opens with the standard chart, its VAT quarters and year end, its deadlines, its fee on the Fees page, and a customer record in the firm's own books. Every step is on the firm's audit trail, the signature as the client's.

1i½. Bringing a practice's clients over (/clients/import), 2 minutes

• Client files → Bring clients over: the practice's client list from its own spreadsheet (CSV): company name, country, registration and VAT numbers, TIC, incorporation date, year end, VAT quarter, what it does, who looks after it, its fee and the month its books start in Ledgerline. The columns are recognised from their headings, in English or Greek.
• Every row is checked before anything is saved: a bad HE number or VAT check digit is caught, a company already a client is left alone, and each shows the kind of business its Ledgerline will be shaped to (from the column, or from what it does).
• Bring over: every company's books open at once, in its country's terms and shaped to its kind of business, with its fee in the practice's books. Deadlines start from the month its books start, so nothing earlier shows as overdue. Each client file says it was brought over: the engagement letter and due diligence are recorded as they come up for review. 300 clients import in about 7 seconds.
• Next: invite their owners (/clients/owners, also Owners on Ledgerline on Client files): every client's owner, at the contact on its file, as joined, invited or still to invite. Tick them (all are ticked) and Invite: Ledgerline makes the links and sends nothing itself. The practice sends them from its own email: Open in email for each person, or Download for a mail merge, a CSV with each person's message ready for Outlook, Word or Gmail. Someone who runs several of the clients (a holding company and its trading company) gets one link that joins them to all of them. A new link replaces the one sent before; 100 invitations take under half a second.
• The owner opens the link, makes their account, and lands on their company's Home with a welcome and Getting started: their logo on the invoices, their customers (patients at a clinic), the first invoice, a receipt, the bank statement. Each step ticks itself off when the books show it, and Hide puts the list away for that person. The practice sees the same steps on a new client's Home, with inviting the owner first; they show for a company's first 90 days.

1j. VAT numbers (/vat-numbers), 2 minutes

• A sale to a business in another EU state is zero-rated only if the customer's VAT number is valid in VIES, the European Commission's register; the tax office asks for the proof. This page checks any EU number live: type IE6388047V and VIES answers "Google Ireland Limited" with its address. Shape and check digit are checked as you type, for all 27 states and Northern Ireland, so a mistyped digit is caught before VIES is asked.
• The registers strip is live: member states take theirs down for maintenance, and the page says which (Greece was down on 22 Oct).
• Every EU customer and supplier across all the clients, with the last check: Pixelforge's Nordlicht confirmed last week (Germany discloses no name), Brabant last confirmed in June so due again, Atelier Lumière never. Check every number now re-checks them all and keeps every answer.
• On Nimbus Cloud Services (Pixelforge's suppliers), Check in VIES: the number is registered to "Stratocumulus Hosting B.V.", and the page says so. The same check sits on each EU customer, and on every reverse-charge invoice; the VIES statement has a "Confirmed in VIES" column, and Pixelforge's Home lists the EU customers to confirm.
• Every check is kept, on the company's audit trail, with Copy as evidence. The client companies are invented, so their answers come from a demo register and say "Demo answer"; any real number goes to the real VIES. Saving a customer or supplier with a mistyped EU number is refused.

1k. Year end and audit (a company's Year end, under Reports & tax), 3 minutes

• Kalamies Dental: 2025's turnover and total assets, and 2024's, are within the limits, so its accounts may be reviewed (ISRE 2400) instead of audited, and the company has chosen that. The page shows why, figure by figure. Its 2026 year began before 6 February 2026, so the old €200,000 turnover limit still applies to it; the €300,000 limit starts with 2027.
• Larnaka Roast: 2024's turnover was over the limit, so 2025 must be audited. The steps run in the order the law sets, each with its due date. The annual general meeting is past its date (15 months after the last one) and shows in red. Record dates: a report dated before the board approved the accounts is refused (ISA 700).
• Before it goes to the auditor: the trial balance, the lock date, bank lines, VAT returns, the manual journals an auditor will ask about (ISA 240; opening balances, agreed to last year's accounts under ISA 510) and the audit trail.
• Download the audit file: one ZIP of CSVs (trial balance, P&L, balance sheet, general ledger, journal, manual journals, receivables and payables at the year end, bank, VAT returns, the audit trail), and a read-me with the checks and each file's SHA-256.
• Troodos Gold is audited by the practice itself: the page says what the IESBA Code (section 601) asks of a firm that audits books it keeps.
• People (under More): invite the auditor with the role Auditor. They read the books and take the audit file; the database refuses any change.

1l. Calendar (/calendar, and Calendar in each company), 2 minutes

• What is due, on its day: month, week or agenda. Across all clients it opens on the filing deadlines; Everything adds each client's tasks, invoices falling due (one line per client per day) and quotes running out. Pick a client to see that one alone; inside a company it is that company's.
• Agenda: what is overdue first (Kalamies' slipped provisional tax, Mesogeios' AML review), then each day.
• Subscribe in your calendar: a private link for Google, Outlook or Apple Calendar showing what the page shows, given once; making a new one stops the old. On the laptop, Apple Calendar can read it; Google and Outlook read from their own servers, so they need Ledgerline online.

1m. Two UK clients, 3 minutes

• Each company has its own country: its currency, chart of accounts, VAT rates, VAT return and deadlines follow it. Switch to Thames Edge Joinery (Reading): pounds, the UK chart, VAT at 20%, 5% or 0%.
• It is a joinery subcontractor: its sales to contractors are under the CIS domestic reverse charge (the invoice says "customer to pay the VAT to HMRC"), and it buys in labour the same way. VAT returns: HMRC's nine boxes, the construction reverse charge in boxes 1 and 4, and a repayment each quarter.
• Record a bill from Wren Site Labour: the reverse charge is a choice, because each kind fills different boxes (services from abroad, construction, imports under postponed VAT accounting).
• Willow & Wren Design (Bristol) is on the Flat Rate Scheme at 12%: its return is 12% of the turnover with its VAT, less VAT on the one computer over £2,000. Mark as filed: the rest of the VAT charged moves to account 265, Flat Rate Scheme surplus. Its Company settings hold the scheme.
• Their Deadlines are HMRC's and Companies House's; their Year end tests the small-company audit exemption. Submitting to HMRC through Making Tax Digital is the next step, built against HMRC's sandbox first.

1n. Payroll (a company's Payroll, under Money), 3 minutes

• Aegean Blue Marine: four employees, each with their salary, tax and social insurance numbers, and what the previous payroll paid them from January to September, brought forward so this year's tax is right from the first month in Ledgerline. Nikos Charalambous declared two children on TD59.
• Run October 2026's payroll: every payslip worked out as a draft. Social insurance 8.8% each way up to the month's maximum, GESY 2.65% and 2.9%, the employer's funds, and income tax: the year's tax at today's pay, less what has been withheld. To pay by 30 Nov 2026 says what goes to Social Insurance Services, what to the Tax Department with the monthly TD7, and what to the employees.
• Overtime, a bonus or commission this month: add €250 for Andri Ioannou and the month is worked out again, tax included.
• Approve and post October 2026: one entry in the books on the pay date (wages and contributions against what is owed to each), and the month is fixed. Then Payslips (a PDF, a page each, with the year to date), Salary payments file (SEPA, marked as salaries, to upload to the bank) and TD7 and Social Insurance figures (a CSV, employee by employee).
• December pays the 13th salary on its own: insurable only up to what is left of the year's maximum. A UK company has no Payroll in its menu yet.

2. AI capture (/capture), 4 minutes

• Drag all four files from demo-files/ in at once:
  • 01-greek-marine-fuel-invoice.pdf: Greek, addressed to ΑΙΓΑΙΟ ΜΠΛΟΥ…
  • 02-two-invoices-in-one-pdf.pdf: two invoices for two different clients
  • 03-photographed-print-shop-invoice.jpg: a phone photo, in Greek
  • 04-eu-reverse-charge-invoice.pdf: a Dutch supplier charging no VAT
• Watch each row read in parallel. Then: five invoices found from four files, each routed to its client by the customer's VAT number, Greek transliterated, supplier matched (or new), accounts suggested from that client's own chart.
• Open Review on the Nimbus invoice: the six checks (lines add up, VAT per rate, net + VAT = total, Cyprus rates, supplier VAT number, not a duplicate) are Ledgerline's own arithmetic, not the AI's word. The reverse charge is detected: VAT due and reclaimed, boxes 1, 4, 7 and 11B.
• Show the document beside the extraction. Change a client with Move here to show the draft re-making itself in another company's books.
• Post all: every bill posts to the right company's ledger. Open one from "Posted from capture" and scroll to How it posted: the double entry.

3. Bank reconciliation, 3 minutes

• Dashboard → Aegean Blue's bank lines (or Bank in its books).
• "The bank should show" agrees with "The bank says": the sum explains itself.
• 18 of 19 October lines have a sure match: the bank's text names the invoice or bill and the amount agrees, or it is a card payment coded the same way many times before. Match all 18: one press.
• The one left is a part payment (Blue Horizon paid half an invoice): press the arrow, Invoices, take the half; the invoice stays open for the rest.
• Bulk coding: tick several lines, pick an account and VAT rate, Code all.
• Import: Import statements → demo-files/05-aegean-blue-boc-statement-21-oct.csv (a Bank of Cyprus-style CSV). Import it a second time: nothing doubles.
• A year's statements at once: choose or drop any number of files (CSV, CAMT.053, MT940 or OFX). They line up in date order, each with its opening and closing balance, and each is checked against the one before it (and the first against the last one already imported): one that doesn't follow on says so, as does a month with nothing, before anything is saved. A file for another account (its IBAN not this one's) is left out, as are lines in another currency, pending or declined payments and card holds. Airwallex's Balance Activity Report is read by its documented columns, and the headings Revolut, Wise, Starling, Monzo, Lloyds and NatWest are known to use are recognised (still to be checked against real exports); a CSV whose balances move the other way to its amounts says money in and out look the wrong way round. They import together, all or none, each its own import to undo (a long one's parts as one).
• Invoice money received: payments in with nothing in the books for them (a business moving over from its bank statements, say) become invoices in one go: to the payer as customer (one already kept when its name is in the bank's words, "ACME LTD INV 1043" and "Acme Limited" alike), for what was sold, with the VAT the invoice form would charge that customer worked back from the total, in a number series of their own (TG-R2026-0001), and matched to the payment, so each is paid. Only payments from customers already kept start ticked. One with a note starts unticked and is matched or coded on the reconcile page instead: it looks like it pays an invoice already raised, is already in the books, comes from a customer who owes money, is there twice, was coded otherwise before, or isn't a sale (interest, a loan, a refund, tax, card takings, a transfer, the company's own money). One line: its arrow → Raise an invoice. Undo on such an invoice voids it and puts its payment back.

4. Reports, 3 minutes

• VAT return (Reports → VAT return): the Jul–Sep return is on screen, box by box, due 10 Nov. Returns are filed in the Tax Department's own portal, Tax For All (https://taxforall.mof.gov.cy, signed in to with CY Login), which has no way in but its own screens: so beside every box is a copy button that gives the amount as Tax For All takes it (2068.79), and File it on Tax For All, step by step says what to do in order, with Copy every box for the file. Type Tax For All's reference beside Mark as filed and lock the period: the lock date moves to 30 Sep and nothing in the quarter can change any more (the database refuses, whatever the route); the return keeps the boxes as filed and the reference, and the audit trail records both. Back on the dashboard the return shows as filed.
• Pixelforge Studio VAT return: services to EU clients in box 8B, the reverse charge on its Dutch cloud supplier in 1, 4, 7 and 11B. Its VIES statement (Reports) lists the same sales by customer VAT number, as the recapitulative statement asks for them, and says that it agrees with 8B.
• P&L (try "month by month"), balance sheet, trial balance, general ledger, cash flow: one ledger, so they always agree. Every figure drills down.
• Reports → Business overview: twelve months of charts, the books health checks, Explain the figures (Claude reads totals only, never a name) and Ask the books, e.g. "What did we spend on fuel this year, month by month?"
• More → Journals: the entries written by hand (opening balances, accruals, corrections). Open one to edit it, remove it, or Reverse it: every debit becomes a credit, dated the first of the next month. A journal inside a locked period can only be reversed.
• Audit trail: every posting, match, lock and filing on a SHA-256 hash chain, with who did it; "The chain is intact" is recomputed on every view.

5. White label (Practice settings), 1 minute

• Type the accountant's firm name and initials, pick their colour: the page takes the colour as it is picked. Save the brand: every screen is now their product, with "Powered by Ledgerline" in the corner.

6. Ledgerline compared (/compare), 2 minutes

• Open it from Powered by Ledgerline at the bottom of the menu.
• One page against Balabook, from its public site (checked 20 Oct 2026). "Not stated" means its pages don't say, not that it lacks it.

Cyprus rules Ledgerline follows (checked 26 October 2026)

The dates and tests are in src/lib/domain (deadlines.ts, vat.ts, extensions.ts, audit.ts), and npm run check:rules checks each one.

• Company tax return (IR4): for tax years to 2025, 31 March two years on; from tax year 2026, 31 January two years on (13 months), with the balance of tax. For years to 2025 the balance is paid by 1 August of the following year. Provisional tax: 31 July and 31 December. Corporation tax is 15% from 2026.
• VAT: the return and payment by the 10th of the second month after the quarter; VIES by the 15th of the month after a month with EU services.
• Payroll: the monthly TD7, Social Insurance, GESY and tax withheld by the end of the following month; the employer's TD7 by 31 May of the next year.
• What payroll works out (payroll-cy.ts, checked 27 October 2026): social insurance 8.8% from the employee and 8.8% from the employer on earnings up to the month's maximum (€5,551 in 2025, €5,742 in 2026), and on the same earnings the Redundancy Fund (1.2%) and the Human Resource Development fund (0.5%); GESY 2.65% and 2.9% on all pay up to €180,000 a year; the Social Cohesion Fund, 2% on all pay. A 13th salary is declared on its own, insurable only up to what is left of the year's maximum. Income tax from 2026: nothing to €22,000, then 20%, 25% (from €32,000), 30% (from €42,000) and 35% (over €72,000); 2025's bands start at €19,500. Social insurance and GESY are deducted up to a fifth of the pay, and so is what the employee declares on TD59. The Central Holiday Fund is left out: most employers are exempt and run their own leave.
• Official extensions (extensions.ts, kept from the announcements): 2024 company tax returns and the 2025 employer's return to 30 November 2026; the VAT return for the quarter to 30 November 2025 and December 2025's VIES to 20 January 2026; the quarter to 30 June 2026 and July 2026's VIES to 20 August 2026.
• Registrar (Companies Law, Cap. 113): financial statements within 12 months of the year end (s.142(2)); the annual return (HE32) made up to the day after 18 months from incorporation and each year on, filed within 28 days (s.120); an AGM every year, at most 15 months apart (s.125).
• Audit or review (s.152A): every company is audited, except that a private company within the limits in two consecutive years may choose a review under ISRE 2400. The limits are turnover (with rent, interest, dividends and royalties) up to €200,000 for years beginning before 6 February 2026 and €300,000 from then, and total assets up to €500,000. A review is not open to a group that consolidates, nor to a company regulated by the Central Bank, CySEC or the Superintendent of Insurance, or holding a qualifying stake in one.
• Size (s.141A): micro, small and medium at €450k/€900k/10, €5m/€10m/50 and €25m/€50m/250 (total assets, turnover, employees), with at most one limit exceeded.
• Framework: IFRS as adopted by the EU. A small company may use the Financial Reporting Standard for small-sized entities (s.142(1)(α1)) once ICPAC issues it; it has not yet.

Sources: Cap. 113, consolidated, on CyLaw; PwC Tax Summaries, Cyprus tax administration; EY, Cyprus enacts major tax reform legislation; ICPAC's financial reporting standards-setting committee; PwC Tax Summaries, Cyprus: personal income tax, deductions and other taxes; KPMG Cyprus, maximum insurable earnings for 2026; and, for each extension, the announcement linked in src/lib/domain/extensions.ts.

UK rules Ledgerline follows (checked 27 October 2026)

In src/lib/domain (regimes.ts, vat-uk.ts, deadlines.ts, audit.ts, eu-vat.ts) and uk_vat_figures in the schema; npm run check:rules checks each one.

• VAT: 20%, 5% and 0%, exempt and outside the scope. The return and its payment 1 calendar month and 7 days after the period; under annual accounting, 2 months after the year, with nine payments on account of 10% or three of 25%.
• The nine boxes: reverse charges in boxes 1 and 4: services bought from abroad (and in box 6 and 7), construction services under the CIS domestic reverse charge, and imports under postponed VAT accounting (and in box 7). Credit notes come off boxes 1 and 4. Wages, PAYE and NIC, business rates and dividends are never on a return. Boxes 2, 8 and 9 (Northern Ireland's goods trade with the EU) are not handled yet.
• Flat Rate Scheme: the rate times VAT-inclusive turnover; only single capital purchases of £2,000 or more with VAT are reclaimed; box 6 includes VAT. It cannot be combined with the Cash Accounting Scheme, but has its own cash-based turnover; it can be combined with annual accounting.
• Cash accounting: VAT when customers pay and suppliers are paid, each payment split between net and VAT as its document was.
• Companies House and HMRC: annual accounts 9 months after the year end (the first, for a first period over a year, the later of 21 months from incorporation and 3 months after it); Corporation Tax 9 months and a day after; the Company Tax Return (CT600) 12 months after; the confirmation statement within 14 days of each anniversary. A deadline counted from a month end runs to a month end (Companies Act 2006, s.443).
• Audit exemption: a small company, within two of turnover £15m, total assets £7.5m and 50 employees, for years beginning on or after 6 April 2025 (£10.2m and £5.1m before).
• GB VAT numbers: 9 digits whose check digits pass HMRC's mod 97 test (or the same with 55 added, for numbers issued since 2009). VIES does not hold them; HMRC's own check comes with Making Tax Digital.
• An individual's tax year: 6 April to 5 April.

Sources (GOV.UK): How to fill in your VAT Return (VAT Notice 700/12); import VAT on the return; Flat Rate Scheme and VAT Notice 733; Cash Accounting Scheme; annual accounting deadlines; Company Tax Returns; annual accounts; confirmation statement; audit exemptions.

The front page

public/home.html is Ledgerline's own page: a visitor who isn't signed in sees it at / (src/proxy.ts), with Sign in at the top and Book a demo going to Wolsten Studios; someone signed in goes straight to their dashboard. It began as the landing page artifact and is plain HTML, so it changes without touching the app.

The public demo

Every push to main deploys to Vercel: https://ledgerlinecy.app (www. redirects to it; https://ledger-line-vert.vercel.app is the same deployment). Supabase Auth's site URL is the domain, and its redirect list holds /auth/callback on both addresses; LEDGERLINE_SITE_URL on Vercel is the domain too, for links made without a request to take the host from. With no database of its own it runs the embedded one in the server's temporary folder, so its data is made up, built afresh on each new server (a few seconds on the first visit) and kept only while that server runs. Every page says so. Documents are read from the demo files' recordings only, and Claude is never asked, so it costs nothing however many people try it (HOSTED_DEMO in src/lib/auth/config.ts). Once the variables below are set on Vercel, the same deployment is the live one.

Going live on Supabase

Live, Ledgerline runs on Supabase's Postgres in the EU (Frankfurt), with the same schema and the same access rules as the laptop demo. The laptop demo enforces those rules too: what it shows Maria is what the database lets her see.

Who sees what (row-level security, at the end of src/lib/db/schema.sql):

• A practice's people (practice_staff.user_id) see every company it keeps.
• A client company's own people (company_members) see that company and nothing else, and none of the practice's records about it: its AML file, its fee, the time spent on it. Pixelforge's owner, Nikos Savva, is seeded to show it.
• Nobody signed in sees nothing. Only the database writes the audit trail.
• Every request from a person runs as the role authenticated, with their id in request.jwt.claims, as Supabase runs it (src/lib/db/index.ts). Work done for nobody in particular (a client's private link, the website form, the sanctions list refresh) runs inside asService(), which names why.
• npm run check:tenancy proves it: 78 checks, asked as a partner, as someone at another practice, as a client's owner, as an auditor and as nobody. Against a real Postgres: DATABASE_URL=… CHECK_TENANCY_WIPE=1 npm run check:tenancy (it empties that database first: a throwaway one only).

Signing in (src/lib/auth, src/proxy.ts, src/app/(auth)):

• Live, Supabase Auth: email and password, and an emailed link to set a new one. The proxy refreshes the session and sends anyone not signed in to /sign-in; who someone is, is verified (getClaims) where data is read.
• Nobody signs up on their own. A partner invites the practice's people (Practice settings → People); anyone at the practice, or a company's owner, invites a client company's own people (Company settings → People). The invitation's link (valid 14 days, kept only as a fingerprint) is where they make their account; it is proof the address is theirs, so it also joins them to any other client company the practice has invited that address to. Many owners are invited at once from Owners on Ledgerline (/clients/owners); Ledgerline sends no email itself.
• The laptop demo has no passwords: /sign-in lists its people. Sign in as Nikos Savva to see Ledgerline as a client's owner does.
• tests/supabase-auth.spec.ts drives the Supabase path through @supabase/ssr against tests/support/stand-in-auth.mjs, a stand-in for Supabase Auth's endpoints with a real Postgres behind it. It proves Ledgerline's side, not Supabase's: run it against the real project too.

Setting it up

1. Create a Supabase project in the Frankfurt region (eu-central-1).
2. supabase link --project-ref …, then supabase db push: it applies supabase/migrations, the baseline (generated from schema.sql by npm run supabase:migration) and the link to Supabase Auth.
3. Give the host (Vercel, EU region) the variables at the end of .env.example: DATABASE_URL (the transaction pooler, port 6543), NEXT_PUBLIC_SUPABASE_URL, NEXT_PUBLIC_SUPABASE_PUBLISHABLE_KEY, SUPABASE_SECRET_KEY, LEDGERLINE_SITE_URL, and ANTHROPIC_API_KEY. Made from Vercel instead (the project's Storage → Create Database → Supabase, Frankfurt), the project gets POSTGRES_URL, NEXT_PUBLIC_SUPABASE_ANON_KEY and SUPABASE_SERVICE_ROLE_KEY, which Ledgerline reads as well; only LEDGERLINE_SITE_URL and ANTHROPIC_API_KEY are left to add.
4. In Supabase Auth: turn off "Allow new users to sign up" (accounts come only from invitations), set the Site URL to LEDGERLINE_SITE_URL, and add LEDGERLINE_SITE_URL/auth/callback to the redirect URLs.
5. The Data API can stay on or be switched off: anonymous requests get nothing, and a signed-in one sees only what the rules allow.
6. The first practice and its first partner are made by Wolsten Studios (the admin console is still to come); everyone else is invited: DATABASE_URL=… npx tsx --conditions=react-server scripts/first-practice.mts --practice "Name Ltd" --partner "Full Name" --email [email protected] opens the practice with its own books and prints the partner's link.

Live since 28 October 2026 on the Supabase project Ledger Line (Ireland, eu-west-1), with Vercel's functions beside it in Dublin (vercel.json). Its Data API is off. The baseline and the accounts migration are applied and recorded, so npm run supabase:migration now refuses: a change to the schema is a new, dated migration, and schema.sql follows it.

On 30 October 2026, statements, statement checks, remittance advice and document styles came with two migrations. Apply 20261030120000_statements_and_document_styles.sql before that version goes live: it only adds (each company's colour and terms become its default style), so the version before it keeps working. Apply 20261030120100_drop_invoice_accent.sql once the new version is live. Rehearsed on a copy built from the old schema: after both, the database is the same as one built from schema.sql, column for column.

20261030140000_tighten_rights.sql can run at any time. Supabase's default rights had given the app's role authenticated TRUNCATE (which skips row-level security and the audit trail's append-only guard), REFERENCES, TRIGGER and MAINTAIN on every table, and on every table made later; it keeps only the rows, under the rules. Nobody, the owner included, can now empty the audit trail, and no function, now or later, is open to PUBLIC.

20261030150000_audit_appends_in_turn.sql too: the audit trail is one hash chain for every company, and two transactions appending at once could both link to the same entry, which audit_verify() then reports as a break (shown on a real Postgres, with two connections). An append now waits for the one before it to commit. And 20261031090000_payment_indexes.sql: payments found by their document and bank account through an index. All three go in one paste, 3-tighten-rights.sql, rehearsed on a copy of the live schema.

A migration run by hand in the SQL editor goes in one transaction, with set local lock_timeout = '5s' first (a busy table then stops it, changing nothing, instead of holding the app up), and records itself in supabase_migrations.schema_migrations with its full text, as supabase db push would.

The whole test suite runs against any Postgres too: DATABASE_URL=… npx playwright test (an empty, throwaway database; it is rebuilt with the demo data). On 26 Oct it passed on Postgres 16. The Supabase sign-in test, against the stand-in: DATABASE_URL=… node tests/support/stand-in-auth.mjs in one terminal, then build with NEXT_PUBLIC_SUPABASE_URL=http://127.0.0.1:54321 and the publishable key from node tests/support/stand-in-auth.mjs --keys, and run LEDGERLINE_AUTH_E2E=supabase npx playwright test tests/supabase-auth.spec.ts with the same variables and SUPABASE_SECRET_KEY. For a staging demo on a real project, npm run supabase:demo-users gives the demo's people sign-ins.

Still to do before the first practice signs up

• The admin console for Wolsten Studios: every practice, its subscription (Stripe), suspending one, logged support access.
• Files into Supabase Storage: documents, logos and captures are kept in Postgres today.

At a big practice's scale

LEDGERLINE_DEMO_COMPANIES=400 builds the demo with that many client companies: the eight, then variants of them, each with its own name, numbers, bank account and fifteen months of books generated the same way, its CRM, staff and file following the one it varies. Use it on a throwaway database:

DATABASE_URL=postgres://… LEDGERLINE_DEMO_DATA=1 LEDGERLINE_RESET_ON_START=1 LEDGERLINE_DEMO_COMPANIES=400 npm run start

Measured on 27 October 2026 with 400 clients on Postgres 16 (101,000 bank lines, 365,000 journal lines, 20,000 invoices, 31,000 bills; built in 95 seconds): every company page answers in 15 to 45 ms, and the practice pages (the dashboard, deadlines, calendar, fees, client files, capture) in under 0.6 s, with at most about 1,700 elements on screen. Before this, the dashboard and deadlines took 47 seconds: each bank line's status was worked out by valuing every match. A bank line now knows whether it is matched (bank_line_matched), the dashboard works out VAT only for the clients on screen, deadlines are looked up by company, and the practice pages list the clients that need something first, forty to sixty at a time, with a search by name, HE or VAT number. Pages no longer carry the list of every client for the switcher: the switcher and the timer fetch it when the browser is idle or when first opened (/api/shell/companies), so with 700 clients a company page is about 115 KB, down from 400 KB. The forms that pick a client (the timer, adding time, checking a VAT number) fetch the same list. Time is a hundred entries at a time, and VAT numbers fifty, those to look at first, with a search: 250 KB and 140 KB with 700 clients, down from 1 MB and 865 KB.

If something goes wrong

• Reset demo data at http://localhost:3000/settings?demo=1 rebuilds everything in about two seconds (or npm run demo:reset). The button is hidden from the normal settings page so the product doesn't look like a demo.
• Capture says "AI is not set up": the key isn't in .env.local, or the server was started before it was added. Stop (Ctrl+C) and npm run demo.
• Port 3000 busy: PORT=3001 npm run demo.
• A file fails to read: the row says why; drop it again. Nothing posts until someone presses Post, so a failed read never touches the books.

How it is built

• PDFs (src/lib/documents) are made with react-pdf, one at a time and with Roboto registered afresh for each (pdf-fonts.ts): react-pdf shares a loaded font between documents, and one with much Greek in it otherwise garbles the next (letters drop out). tests/support/pdf-text.ts reads a PDF's text back as a viewer shows it, so the tests catch that.
• Languages (src/lib/i18n): a screen's words are its English, looked up in the Greek dictionary (el.ts) for someone who reads Ledgerline in Greek (app_users.locale): await getI18n() in a server component, useI18n() in a client one, each with the formatters of that language (src/lib/format.ts). Problems the server words in English are read against the dictionary's phrases (t.message); a deadline's title is turned into Greek in i18n/deadlines.ts; what a customer is sent is written in their language in src/lib/documents/messages.ts. Typed figures are read either language's way by plainDecimal (line-math.ts). npm run check:greek checks the dictionary against every translated screen.
• Next.js 16.4 (App Router, Turbopack) on React 19.3 with the React Compiler, run by its Rust port inside Turbopack (next.config.ts), so components are memoised without hand-written useMemo. TypeScript 6.0, the newest the linter's TypeScript parser reads; Tailwind 4; Motion 14.
• src/lib/db/schema.sql: the ledger (journal entries rebuilt by ledger_replace, post_* triggers for invoices, payments, bills, bill payments and bank transactions, lock-date checks, bank reconciliation) with organisation_id on every books table and composite foreign keys, so a document can never post to another company's accounts. Plus the practice, capture, filed VAT returns and the hash-chained audit log.
• src/lib/db/seed.ts: the six fictional companies, generated from a fixed seed. scripts/make-demo-files.mjs renders the invoices in demo-files/.
• Selling (src/app/c/[org]/sales, quotes, credit-notes, customers, items; src/lib/data/sales.ts, src/lib/actions/sales.ts): invoices, quotes and credit notes share one line model (quantity, unit price, discount, VAT), worked out by ledger_document_lines in the database and, identically, by src/lib/domain/line-math.ts on screen. save_invoice, save_quote, and write them; a credit note posts the reverse of a sale, set credit against invoices, and a refund is a bank payment against receivables. The PDFs (invoice, quote, credit note, statement) are (react-pdf, Roboto embedded).